System for the recovery of gaseous dihydrogen from a line discharging liquid dihydrogen from an aircraft

Description

TECHNICAL FIELD

[0001] The present invention relates to the field of distribution of liquid hydrogen and more particularly relates to a system for recovering gaseous hydrogen produced by evaporation of liquid hydrogen during its circulation in a pipe. STATE OF PRIOR ART

[0002] The use of hydrogen in aircraft, for example to power a hydrogen engine, requires the storage of liquid hydrogen and generally requires the distribution or delivery of liquid hydrogen. One difficulty with distributing liquid hydrogen is that a distribution line needs to be at a sufficiently low temperature so that the hydrogen remains in a liquid state. However, when hydrogen begins to flow through an initially empty line, the line is generally at a higher temperature and the liquid hydrogen vaporizes as it flows through the line. The line therefore needs to be cooled before the hydrogen can be used under conditions appropriate for its intended use.Cooling of the pipe must then be carried out during a phase prior to the use of the hydrogen and may involve, for example, circulating liquid hydrogen in the pipe until the hydrogen no longer vaporizes during its circulation.

[0003] However, during such a preliminary cooling step, hydrogen gas is produced and cannot be used for its intended purpose. The hydrogen gas thus produced is then generally vented, resulting in wasted hydrogen.

[0004] It is then desirable to overcome these drawbacks of the state of the art. In particular, it is desirable to provide a solution which makes it possible to prevent the waste of dihydrogen during the transient cooling phase and which makes it possible to use the dihydrogen which is vaporized during said transient cooling phase.

[0005] Document DE 10 2007 023821 A1 describes a system for recovering gaseous dihydrogen according to the prior art. STATEMENT OF THE INVENTION

[0006] A system for recovering gaseous dihydrogen is proposed here, the gaseous dihydrogen being produced by evaporation of liquid dihydrogen in a distribution pipe arranged between a main dihydrogen tank and a dihydrogen consuming device, the distribution pipe comprising a pump for supplying dihydrogen to the dihydrogen consuming device at a predefined temperature and at a predefined pressure, the gaseous dihydrogen recovery system comprising: an auxiliary tank; a bypass pipe, arranged between the distribution pipe and the auxiliary tank, downstream of the pump in a direction of circulation of the dihydrogen in the distribution pipe; a first controlled valve arranged on the bypass pipe; a module for obtaining information representative of a temperature of the dihydrogen in the distribution pipe, upstream of the pump;and a control module of the first controlled valve configured to open the controlled valve when the information representative of the temperature of the dihydrogen in the distribution line is greater than a predetermined value and to close the first controlled valve when the information representative of the temperature of the dihydrogen in the distribution line is less than or equal to the predetermined value.;

[0007] Thus, the gaseous dihydrogen produced by evaporation of liquid dihydrogen circulating in the distribution pipe, during a transient cooling phase of the distribution pipe for example, can be recovered and stored for use. Waste of dihydrogen is thus avoided.

[0008] According to a particular embodiment, the gaseous dihydrogen recovery system further comprises a second controlled valve arranged on the distribution line downstream of the bypass line, and comprises a control module of said second controlled valve configured to close the second controlled valve when the first controlled valve is open and to open the second controlled valve when the first controlled valve is closed.

[0009] According to a particular embodiment, the gaseous dihydrogen recovery system further comprises at least one auxiliary pipe arranged between the auxiliary tank and a dihydrogen storage or consumption device, said dihydrogen storage or consumption device being the main tank and / or the dihydrogen consumer device and / or a third-party device.

[0010] According to a particular embodiment, the gaseous dihydrogen recovery system further comprises a third controlled valve arranged on each auxiliary pipe and comprising a control module of the third controlled valve configured to open said third controlled valve when a use of dihydrogen is required by the dihydrogen storage or consumption device connected by said auxiliary pipe, and to close said third controlled valve otherwise.

[0011] According to a particular embodiment, the auxiliary tank has a storage volume of gaseous dihydrogen provided to maintain the pressure of gaseous dihydrogen inside said auxiliary tank at a value greater than or equal to a predefined pressure.

[0012] According to a particular embodiment, the gaseous dihydrogen recovery system further comprises a discharge pipe connecting the auxiliary tank to one end of the discharge pipe opening into the open air, further comprises a shut-off valve arranged on the discharge pipe and further comprises means configured to open the shut-off valve when the pressure of gaseous dihydrogen in the auxiliary tank exceeds a predefined pressure threshold value and to close the shut-off valve when the pressure of gaseous dihydrogen in the auxiliary tank is less than or equal to said predefined pressure threshold value.

[0013] Also provided is an aircraft comprising a gaseous dihydrogen recovery system in any of its embodiments.

[0014] Also proposed here is a method for recovering gaseous dihydrogen, the gaseous dihydrogen being produced by evaporation of liquid dihydrogen in a distribution pipe arranged between a main tank and a dihydrogen consuming device, the distribution pipe comprising a pump for supplying dihydrogen to the dihydrogen consuming device at a predefined temperature and at a predefined pressure, the method for recovering gaseous dihydrogen comprising: recovering gaseous dihydrogen from the distribution pipe to a bypass pipe, arranged between the distribution pipe and an auxiliary tank, downstream of the pump in a direction of circulation of the dihydrogen in the distribution pipe; storing the gaseous dihydrogen in the auxiliary tank; obtaining information representative of a temperature of the dihydrogen in the distribution pipe, upstream of the pump;and controlling a first controlled valve arranged on the bypass line so as to open the first controlled valve when the information representative of the temperature of the hydrogen in the distribution line is greater than a predetermined value and close the first controlled valve when the information representative of the temperature of the hydrogen in the distribution line is less than or equal to the predetermined value.;

[0015] According to a particular embodiment, the method for recovering gaseous dihydrogen further comprises using the stored gaseous dihydrogen via at least one auxiliary pipe arranged between the auxiliary tank and a device for storing or consuming dihydrogen, said device for storing or consuming dihydrogen being the main tank and / or the device consuming dihydrogen and / or a third-party device. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The above-mentioned and other features of the invention will become more clearly apparent from the following description of at least one exemplary embodiment, said description being given in relation to the attached drawings, among which: [ Fig. 1 ] schematically illustrates a gaseous dihydrogen recovery system; [ Fig. 2A ] schematically illustrates an auxiliary pipe of the gaseous dihydrogen recovery system arranged between the auxiliary tank and a dihydrogen consuming device, according to a particular embodiment; [ Fig. 2B ] schematically illustrates an auxiliary pipe of the gaseous dihydrogen recovery system arranged between an auxiliary tank and a main tank, according to a particular embodiment; [ Fig. 3 ] schematically illustrates a process for recovering gaseous dihydrogen; and [ Fig. 4 ] schematically illustrates an aircraft including the gaseous dihydrogen recovery system. DETAILED PRESENTATION OF IMPLEMENTATION METHODS

[0017] There Fig. 1 thus schematically illustrates a gaseous dihydrogen recovery system 1.

[0018] Gaseous dihydrogen is produced by evaporation of liquid dihydrogen circulating in a distribution pipe 11 arranged between a main tank 10 and a dihydrogen consuming device 19. The main tank 10 is a liquid dihydrogen tank. The dihydrogen consuming device 19 is for example a hydrogen engine, using dihydrogen as fuel. The distribution pipe 11 is intended to convey dihydrogen in a direction of circulation of the dihydrogen, from the main tank 10 to the dihydrogen consuming device 19. According to said direction of circulation of the dihydrogen, the upstream term is defined, with respect to the distribution pipe 11, as a relative position located closer to the main tank 10 while the downstream term is defined, with respect to the distribution pipe 11, as a relative position located closer to the dihydrogen consuming device 19.

[0019] The distribution line 11 comprises a pump 13, for example a high-pressure pump intended to supply the hydrogen consuming device 19. The pump 13 is configured to supply the hydrogen consuming device 19, in other words downstream of said pump 13, with hydrogen at predefined temperature and pressure conditions from liquid hydrogen in order to allow proper operation of the hydrogen consuming device 19. During a nominal operating phase of the hydrogen consuming device 19, the hydrogen must remain in the liquid state in a portion of the distribution line 11 located between the main tank 10 and the pump 13.On the other hand, during a preliminary cooling phase of the distribution pipe 11 during which the walls of the distribution pipe 11 cool in contact with the liquid hydrogen coming from the main tank 10, the hydrogen circulating in the distribution pipe 11 vaporizes. The pump 13 then receives gaseous hydrogen and therefore cannot supply hydrogen at said predefined temperature and pressure conditions.

[0020] The recovery system 1 comprises a bypass line 14, arranged between the distribution line 11 and an auxiliary tank 16 for storing gaseous dihydrogen. The bypass line 14 is connected to the distribution line 11 at a position of said distribution line 11 located downstream of the pump according to the direction of circulation of the dihydrogen in the distribution line 11.

[0021] The recovery system 1 further comprises the auxiliary tank 16 for storing gaseous dihydrogen.

[0022] The recovery system 1 further comprises a first controlled valve 15 arranged on the bypass line 14. The first controlled valve 15 can be open or closed.

[0023] The recovery system 1 further comprises a module 12 for obtaining information representative of a temperature of the dihydrogen in the distribution pipe 11 upstream of the pump 13. The obtaining module 12 is for example a temperature sensor.

[0024] The recovery system 1 further comprises a first control module (not shown) of the first controlled valve 15 configured to open the first controlled valve 15 when the information representative of the temperature of the dihydrogen in the distribution pipe 11 is greater than a predetermined value and to close the first controlled valve 15 when the information representative of the temperature of the dihydrogen in the distribution pipe 11 is less than or equal to the predetermined value.

[0025] The predetermined value is for example a temperature value at which the dihydrogen vaporizes, in other words passes from the liquid state to the gaseous state, and is equal to -252.87°C or 20.28 K. Thus, when the dihydrogen circulating in the distribution pipe 11 upstream of the pump 13 is gaseous, the first controlled valve 15 is open and the gaseous dihydrogen is recovered in the bypass pipe 14. On the other hand, when the dihydrogen circulating in the distribution pipe 11 upstream of the pump 13 is gaseous, the first controlled valve 15 is closed and the liquid dihydrogen remains in the distribution pipe 11.

[0026] When the first controlled valve 15 is open, the dihydrogen recovered in the bypass line 14 flows from the distribution line 11 to the auxiliary tank 16.

[0027] According to an exemplary embodiment, the recovery system 1 further comprises a second controlled valve 151 arranged on the distribution pipe downstream of the bypass pipe. The recovery system 1 further comprises a second control module (not shown) of said second controlled valve 151 configured to close the second controlled valve 151 when the first controlled valve 15 is open. Thus, the recovery of the gaseous dihydrogen circulating in the distribution pipe 11 is maximized since the circulation of the gaseous dihydrogen to the dihydrogen consuming device 19 is prevented. The second control module of said second controlled valve 151 is further configured to open the second controlled valve 151 when the first controlled valve 15 is open, so as to allow the dihydrogen circulating in the distribution pipe 11 to circulate to the dihydrogen consuming device 19.

[0028] The recovery system 1 further comprises at least one auxiliary pipe 17a, 17b, 17c arranged between the auxiliary tank 16 and a device for storing or consuming hydrogen 10, 19, 101. For example, the device for storing or consuming hydrogen is the main tank 10, or the hydrogen consuming device 19 or a third-party device 101.

[0029] According to the example illustrated in Fig. 1 , the recovery system 1 comprises a first auxiliary pipe 17a arranged between the auxiliary tank 16 and the main tank 10, a second auxiliary pipe 17b arranged between the auxiliary tank 16 and the hydrogen consuming device 19 and a third auxiliary pipe 17c arranged between the auxiliary tank 16 and the third-party device 101. The third-party device is for example a hydrogen mixer intended to heat an external flow of hydrogen intended to carry out a heat exchange with a heat transfer fluid so that the heat transfer fluid does not freeze during said heat exchange.

[0030] According to one embodiment, the recovery system 1 comprises a third controlled valve 18a, 18b, 18c arranged on each auxiliary line 17a, 17b, 17c. Each third controlled valve 18a, 18b, 18c is controlled by a third control module associated with the hydrogen storage or consumption device 10, 19, 101 connected by the auxiliary line 17a, 17b, 17c in question.

[0031] The third control module is configured to open the third controlled valve 18a, 18b, 18c when a use of dihydrogen is required by the dihydrogen storage or consumption device 10, 19, 101 in question. The third control module is configured to close said third controlled valve 18a, 18b, 18c when the use of dihydrogen is not required by the dihydrogen storage or consumption device 10, 19, 101 in question.

[0032] For example, the third control module associated with the third controlled valve 18a arranged on the first auxiliary pipe 17a opens said third controlled valve 18a when re-pressurization of the main tank 10 is required, and closes said third controlled valve 18a when re-pressurization of the main tank 10 is not required.

[0033] According to another example, the third control module associated with the third controlled valve 18b arranged on the second auxiliary line 17b opens said third controlled valve when a start-up of the dihydrogen consuming device 19 is required. Said third control module closes said third controlled valve 18b when the start-up of the dihydrogen consuming device 19 is not required, in other words before the start-up of the dihydrogen consuming device 19 or when the start-up is completed.

[0034] According to one embodiment, the auxiliary tank 16 comprises an electric heating device 161. The heating device 161 is configured to increase the temperature of the hydrogen gas stored in said auxiliary tank 16 when a temperature of the hydrogen gas stored in the auxiliary tank 16 is lower than a predefined temperature. According to one example, the recovery system 1 comprises the second auxiliary line 17b, the hydrogen consuming device 19 is a hydrogen engine and the predefined temperature is a minimum temperature of hydrogen gas necessary to start a hydrogen engine. Thus, it is possible to obtain and use hydrogen gas at a predefined temperature to start the hydrogen engine.

[0035] According to one embodiment, the auxiliary tank 16 has a storage volume of gaseous dihydrogen provided, designed and adapted to maintain the pressure of gaseous dihydrogen inside said auxiliary tank 16 at a value greater than or equal to a predefined pressure, for example 3 bar. The volume of the auxiliary tank 16 is designed taking into account a quantity of gaseous dihydrogen that can be recovered in said auxiliary tank 16 during the preliminary cooling phase of the distribution pipe 11.

[0036] According to one embodiment, the recovery system 1 further comprises an evacuation pipe 162 connecting the auxiliary tank 16 to an end 1621 of the evacuation pipe 162 opening into the open air, for example to the exterior E of an aircraft 4. The recovery system 1 further comprises a shut-off valve 163 arranged on the evacuation pipe 162 and comprises means for opening the shut-off valve 163 when the pressure of gaseous dihydrogen in the auxiliary tank 16 exceeds a predefined pressure threshold value and for closing the shut-off valve 163 when the pressure of gaseous dihydrogen in the auxiliary tank 16 is less than or equal to said predefined pressure threshold value. Thus, the accumulation of gaseous dihydrogen beyond a predefined pressure is prevented.According to one example, the shut-off valve 163 opens under a mechanical action resulting from a pressure exerted by a gas coming from the auxiliary tank 16 when said pressure exceeds the predefined pressure threshold value and closes otherwise. According to another example, the means for opening and closing the shut-off valve comprise a pressure sensor making it possible to obtain information representative of the pressure inside the auxiliary tank 16 and comprise a control module for the shut-off valve 163. The control module for the shut-off valve 163 is configured to open the shut-off valve 163 when the information representative of the pressure of dihydrogen in the auxiliary tank 16 exceeds the predefined pressure threshold value and to close the shut-off valve 163 otherwise.The control module of the shutoff valve 163 comprises a processor capable of executing instructions loaded into a memory, causing the implementation of the steps of opening and closing the shutoff valve 163. The control module may comprise a DSP (Digital Signal Processor) type processor or a microcontroller, or a dedicated machine or electronic component (chip) or a dedicated set of electronic components (chipset), for example an FPGA (Field Programmable Gate Array) component or ASIC (Application Specific Integrated Circuit). Generally speaking, the control module of the shutoff valve 163, like each control module of a valve described herein, comprises electronic circuitry adapted and configured to implement the operations, methods and steps described herein in relation to said control module.

[0037] There Fig. 2A schematically illustrates the second auxiliary pipe 17b of the recovery system 1 arranged between the auxiliary tank 16 and the hydrogen consuming device 19, according to a particular embodiment.

[0038] According to said particular embodiment, said second auxiliary pipe 17b comprises a gaseous dihydrogen pressure regulator 21. The pressure regulator 21 is for example a pressure limiter such as an orifice arranged in the second auxiliary pipe 17b.

[0039] Thus, a variation in pressure of the gaseous dihydrogen in the auxiliary tank 16 and in the second auxiliary pipe 17b resulting from a variation in the volume of gaseous dihydrogen accumulated in the auxiliary tank 16 has a limited effect during an injection of gaseous dihydrogen, via said second auxiliary pipe 17a, into the dihydrogen consuming device 19.

[0040] There Fig. 2B schematically illustrates the first auxiliary pipe 17a of the recovery system 1 arranged between the auxiliary tank 16 and the main tank 10, according to a particular embodiment.

[0041] According to said particular embodiment, said first auxiliary pipe 17a comprises a mass flow controller 22. The mass flow controller 22 makes it possible to control a mass flow of gaseous dihydrogen circulating to the main tank 10. Thus, it is possible to control the flow rate of gaseous dihydrogen injected into the main tank 10 in order to ensure that the quantity of gaseous dihydrogen injected into said main tank 10 is sufficient to allow re-pressurization of said main tank 10.

[0042] There Fig. 3 schematically illustrates a process for recovering gaseous dihydrogen.

[0043] According to one embodiment, the gaseous dihydrogen recovery method is triggered at regular intervals, for example every second.

[0044] In a step 301, the module 12 for obtaining information representative of a temperature of the dihydrogen in the distribution pipe 11 upstream of the pump 13 obtains said information representative of a temperature of the dihydrogen.

[0045] In a following step 302, the first control module of the first controlled valve 15 compares said information representative of a dihydrogen temperature with the predetermined temperature value. If the information representative of a dihydrogen temperature is greater than the predetermined value, the first control module performs a step 303. Otherwise, the first control module performs a step 306.

[0046] In step 303, the first control module of the first controlled valve 15 opens said first controlled valve 15 or keeps it open when said first controlled valve 15 is already open.

[0047] According to a particular embodiment, when the recovery system comprises the second controlled valve 151, the second control module closes or maintains the closure of said second controlled valve 151.

[0048] In a following step 304, the gaseous dihydrogen from the distribution line 11 is recovered in the bypass line 14.

[0049] In a following step 305, the gaseous dihydrogen recovered in the bypass line 14 is stored in the auxiliary tank 16.

[0050] In step 306, the control module of the first controlled valve 15 closes said first controlled valve 15 or keeps it closed when said first controlled valve 15 is already closed.

[0051] According to a particular embodiment, when the recovery system comprises the second controlled valve 151, the second control module opens or maintains the opening of said second controlled valve 151.

[0052] There Fig. 4 schematically illustrates the aircraft 4 comprising the gaseous dihydrogen recovery system 1, particularly advantageous for use on board an aircraft insofar as it makes it possible to optimize the consumption of dihydrogen by reducing losses.

Claims

1. Gaseous dihydrogen recovery system (1) comprising a distribution duct (11) arranged between a main tank (10) and a dihydrogen consumer device (19), the distribution duct (11) comprising a pump (13) for supplying dihydrogen to the dihydrogen consumer device (19) at a predefined temperature and at a predefined pressure, the gaseous dihydrogen being produced by evaporation of liquid dihydrogen in the distribution duct (11), the gaseous dihydrogen recovery system (1) comprising: - an auxiliary tank (16), - a bypass duct (14) arranged between the distribution duct (11) and the auxiliary tank (16), downstream of the pump (13) in a direction of circulation of the dihydrogen in the distribution duct (11), - a first controlled valve (15) arranged on the bypass duct (14), - a module (12) for obtaining information representative of a temperature of the dihydrogen in the distribution duct (11), upstream of the pump (13), and - a control module of the first controlled valve (15) configured to open the controlled valve when the information representative of the temperature of the dihydrogen in the distribution duct is greater than a predetermined value and to close the first controlled valve when the information representative of the temperature of the dihydrogen in the distribution duct is less than or equal to the predetermined value.

2. Gaseous dihydrogen recovery system according to Claim 1, further comprising a second controlled valve (151) arranged on the distribution duct (11) downstream of the bypass duct (14), and comprising a control module of said second controlled valve (151) configured to close the second controlled valve (151) when the first controlled valve (15) is open and to open the second controlled valve (151) when the first controlled valve (15) is closed.

3. Gaseous dihydrogen recovery system according to Claim 1 or 2, further comprising at least one auxiliary duct (17a, 17b, 17c) arranged between the auxiliary tank (16) and a dihydrogen storage or consumption device (10, 19, 101), said dihydrogen storage or consumption device being the main tank (10) and / or the dihydrogen consumer device (19) and / or a third-party device (101).

4. Gaseous dihydrogen recovery system (1) according to Claim 3, further comprising a third controlled valve (18a, 18b, 18c) arranged on each auxiliary duct (17a, 17b, 17c) and comprising a control module of the third controlled valve (18a, 18b, 18c) configured to open said third controlled valve when a use of dihydrogen is required by the dihydrogen storage or consumption device (10, 19, 101) linked by said auxiliary duct (17a, 17b, 17c), and to close said third controlled valve otherwise.

5. Gaseous dihydrogen recovery system (1) according to any one of Claims 1 to 4, wherein the auxiliary tank (16) has a gaseous dihydrogen storage volume provided to keep the gaseous dihydrogen pressure inside said auxiliary tank (16) at a value greater than or equal to a predefined pressure.

6. Gaseous dihydrogen recovery system (1) according to any one of Claims 1 to 5, further comprising a discharge duct (162) linking the auxiliary tank (16) to an end (1621) of the discharge duct (162) that emerges in the open air, further comprising a shut-off valve (163) arranged on the discharge duct (162) and further comprising means configured to open the shut-off valve (163) when the gaseous dihydrogen pressure in the auxiliary tank (16) exceeds a predefined pressure threshold value and to close the shut-off valve (163) when the gaseous dihydrogen pressure in the auxiliary tank (16) is less than or equal to said predefined pressure threshold value.

7. Aircraft (4) comprising a gaseous dihydrogen recovery system (1) according to any one of Claims 1 to 6.

8. Gaseous dihydrogen recovery method, the gaseous dihydrogen being produced by evaporation of liquid dihydrogen in a distribution duct (11) arranged between a main tank (10) and a dihydrogen consumer device (19), the distribution duct (11) comprising a pump (13) for supplying dihydrogen to the dihydrogen consumer device (19) at a predefined temperature and at a predefined pressure, the gaseous dihydrogen recovery method comprising: - recovering (304) gaseous dihydrogen from the distribution duct to a bypass duct, arranged between the distribution duct and an auxiliary tank, downstream of the pump in a direction of circulation of the dihydrogen in the distribution duct, - storing (305) the gaseous dihydrogen in the auxiliary tank, - obtaining (301) information representative of a temperature of the dihydrogen in the distribution duct, upstream of the pump, and - controlling (302) a first controlled valve arranged on the bypass duct so as to open (303) the first controlled valve when the information representative of the temperature of the dihydrogen in the distribution duct is greater than a predetermined value and to close (306) the first controlled valve when the information representative of the temperature of the dihydrogen in the distribution duct is less than or equal to the predetermined value.

9. Gaseous dihydrogen recovery method according to Claim 8, further comprising: - using the stored gaseous dihydrogen via at least one auxiliary duct arranged between the auxiliary tank and a dihydrogen storage or consumption device, said dihydrogen storage or consumption device being the main tank and / or the dihydrogen consumer device and / or a third-party device.